Study on the jetting characteristics of an underwater explosion bubble collapsing near a floating body

This study explores the dynamic behavior and jet characteristics of underwater explosion (UNDEX) bubble oscillating near a rigid floating body using the arbitrary Lagrangian–Eulerian (ALE) method. Experiments on UNDEX bubble oscillating in a free field or oscillating near a rigid floating body in an explosion tank are used to validate the effectiveness of the ALE method in simulating the behaviors of high pressure bubble oscillating near a boundary in water. The numerical results are in good agreement with the experimental data. On this basis, the distribution of the field pressure and velocity of the oscillating bubble are further analyzed in detail. The evolution characteristics of the bubble jets are discussed for various values of the stand-off distance and explosion attack angle. The results reveal that a bubble produces two jet patterns for close stand-off distances (from γD=0.800 to γD=1.336) and attack angles of 0°, 45°, 75°, and 90°. The first bubble jet results in an annular splitting of the bubble, while the second jet is pointed toward the floating body. The aim of this study is to provide a reference for further understanding the jet dynamics of UNDEX bubble collapsing near a structure and the effective attack on ship sides.